Diabetes is a group of diseases marked by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. There are 23.6 million people in the United States, or 8% of the population, who have diabetes. The total prevalence of diabetes has increased 13.5% since the 2005-2007 time period. Diabetes can lead to serious complications and premature death, but there are well-known products available for people with diabetes to help control the disease and lower the risk of complications.
Treatment options for people with diabetes include specialized diets, oral medications and/or insulin therapy. The primary goal for diabetes treatment is to control the patient's blood glucose (sugar) level in order to increase the chances of a complication-free life. It is not always easy, however, to achieve good diabetes management, while balancing other life demands and circumstances.
Currently, there are two principal modes of daily insulin therapy for the treatment of type 1 diabetes. The first mode includes syringes and insulin pens that require a needle stick at each injection, typically three to four times per day, but are simple to use and relatively low in cost. Another widely adopted and effective method of treatment for managing diabetes is the use of a conventional insulin pump. Insulin pumps can help the user keep their blood glucose levels within target ranges based on their individual needs, by continuous controlled infusion of insulin. By using an insulin pump, the user can match their insulin therapy to their lifestyle, rather than matching their lifestyle to how an insulin injection, for example, is working for them.
Conventional insulin pumps are capable of delivering rapid or short-acting insulin 24 hours a day through a catheter placed under the skin. Insulin doses are typically administered at a basal rate and in a bolus dose. Basal insulin is delivered continuously over 24 hours, with the goal of keeping one's blood glucose levels in a consistent range between meals and overnight. Some insulin pumps are capable of programming the basal rate of insulin to vary according to the different times of the day and night. Bolus doses are typically administered when the user takes a meal, and generally provide a single additional insulin injection to balance the carbohydrates consumed. Some conventional insulin pumps enable the user to program the volume of the bolus dose in accordance with the size or type of the meal consumed. Conventional insulin pumps also enable a user to take in a correctional or supplemental bolus of insulin to compensate for a low blood glucose level at the time the user is calculating a meal bolus.
There are many advantages of conventional insulin pumps over other methods of diabetes treatment. Insulin pumps deliver insulin over time rather than in single injections and thus typically result in less variation within the blood glucose range that is recommended by the American Diabetes Association (ADA). Conventional insulin pumps reduce the number of needle sticks which the patient must endure, and make diabetes management easier and more effective for the user, thus considerably enhancing the quality of the user's life. Insulin pumps however can be cumbersome to use and are typically more expensive than other methods of treatment. From a lifestyle standpoint, the conventional pump, tubing, and infusion set may be inconvenient and bothersome for the user.
New advances in insulin therapy provide “wearable” drug infusion devices that are lower in cost and more convenient and comfortable to use than conventional insulin pumps. Some of these devices are intended to be partially or entirely disposable, and in theory provide many of the advantages of conventional insulin pumps without the initial high cost and inconvenience of conventional insulin pumps.
Wearable medical devices capable of performing similar functions as conventional insulin pumps are becoming increasingly more prevalent, but are still high in cost. While the initial cost of each wearable medical device is much lower than conventional insulin pumps, the cost for providing drug therapy over an entire year using the wearable medical devices is magnified due to the short duration of use of such medical devices. Common wearable medical devices are typically disposed of after a maximum of 3 days in operation. Some driving factors for the duration of use for such medical devices include the viability of the infusion site for a prolonged period and the challenges of reasonably providing an adequate supply of insulin over such a prolonged period, as well as efficiently providing a durable power source over the extended life of the device. Extending the use of a wearable medical device to last from 5-7 days would greatly reduce the daily cost of therapy, thus enabling a larger population to afford the conveniences provided by such therapy. Therefore, the availability of such wearable medical devices may be increased if the daily cost of such therapy were reduced.
Accordingly, there is a need in the art for extending the duration of use of wearable medical devices, thus providing more cost-effective drug therapy, so that many more diabetes patients can benefit from the advantages these devices provide.
Additionally, most wearable medical devices available in the art are typically referred to as either “smart” or “simple” medical devices. “Smart” patch pumps commonly available in the art typically receive instructions from and/or transmit patient data to an intelligent controller or host device, which requires either wireless or tethered communication between the pump and controller. “Smart” patch pumps are typically larger in size than “simple” patch pumps, heavier and more expensive due to the additional components necessary for providing communication with the host device. Additionally, typical “smart” devices require user interaction for blood glucose monitoring, bolus calculation, and dose programming, which add complexity and risk to the intended use of these devices. “Simple” patch pumps commonly available, on the other hand, typically provide only a preset basal dose. For many users, the level of complexity for a “smart” device is unacceptable, but their therapeutic requirements cannot be satisfied with a “simple” patch pump. Therefore, there is a need for providing specialized insulin therapy, not available from a “simple” patch pump, without the added cost and complexity of a “smart” patch pump.